Springing suspension device for cycles



C. BRUNO. SPRINGING SUSPENSION DEVICE For: CYCLES. APPLICATION -FILED APR.5. 1913.v

1 ,4 1 2,0 1 2. Patented Apr. 4, 1922.

CARLO BRUNO, or TURIN, ITALY.

c srnINsING SUSPENSION DEVICE ron. crtins.V

(GRANTED UNDER THE PROVISIONS 0F ACT OF MARCH 3, 192141 STAT. L., 1313).

To all whom it may concern:

Be it known that I, CARLO BRUNO, engineer, of Turin, Italy, have invented certain new and,useullmprovements in Springing Suspension Devices forCycles, (for 'which I Ahave liled an application in Italy April 6,;1912,) of which the following is a I'ull, clear, and exact specication.

The invention relates to elastic suspension devices for bicycles, motorcycles, and the like, whose front and rear Jforks are made up of two parts of suitable length, the parts beingpivotally connected and subjected to the'aotionof a leaf spring. Y

4Elastic suspension devicesy arealready known which inv addition to thelmentioned parts, are provided with counter-springs which exert a brakingaction uponthe retrogressive movement of SaidleaI' spring.

The principal object or" this invention consists therein, to provide a member with a rolling surface of suitable curvature bearingupon saidleaf spring, such that an 1ncreasing resistanceis offered 1n proportion to the increase ofthe forces which tend to turnone ofthe parts of the forks with' relation -to the other. .1 'Y Another object of the invention is to provide a similar member with a rolling surface of suitable curvature for said counterspring, whereby arbraking action'with increasing energy upon the retrogres'sive move ment of the leaf spring is obtained. Y Othern objects will become more, apparent by .reference'to the drawings, the specifica' tion and the claims forming part thereof.Y ,'One preferred embodiment of the invention is indicated in the drawings, 4in wlnchl- Fig. l is a diagrammatic',illustration ofa bicycle to which the principle of the inventionhas been applied.

Fig. 2 is a sectional planfand Fig. 3 an elevational vie'wof a practical embodiment of the invention as appliedto the front fork of a bicycle. v 9

i Fig. 4; is an' elevational view of the rear orkfo a lbicycle equipped VVwith an elastic suspension device.

With reference to Fig-.1, thevfront Jfork is shown as comprising the parts l-2 and 2-3,'pivoted at 2 so that the front wheel 1l, infrisinginto position et indicated in dotted In one of vthese linesin F ig.` l, under the inuence of a jolt,

heseparts are pivotal connections therear Specification of Letters Patent. Y Patented API-4, 1922 Application led April 5, 1913. SerialNo. 759,098.

teract the forces which tend to raise the Y wheels, whereby the parts of lthe yfork 'are i -K Y f turned with respect to each other, a resistance 1n the form of a spring is appliedto the pivotal jointof the parts ofthe forks,

such that the turning movement 'of one 0I' the Y.parts isr resiliently opposed by the spring Y which shuntsv the rt pivotal connection of the Vpa s.; Y' Y .In Figs. 2.and 3 a practical embodiment is l .illustrated as applied to the front fork of a" bicycle, motorcycle, orthe like.` The front fork comprises the relatively long part '1 and the shorter part 3, Whichlatter is provided one of its extremitiesv with an lintegral pivot-pin 2, which enters the Vhub 28 formed on the long part l of the front fork. The other extremity of the part 3 is formed into `a hub 42 having a square aperture'inwhich sov the square end 31'of ahollow spindle'is vitted. .(This spindle has not been shown in Fig. 3 for the sake of Vclearness) Bymeans of the bolt 29 which passesA through Athe axial hole 1n spindle '30, the Yrods or' parts 'at both sides of the wheeland thespindleO are irmlyconnected together. The spindle 30thusacts as aspacing member and insures A the centered position of the'vvheel, even when lifted.' To the part l'a small link 'l5 is pivotally connected, and a similar Vlink 16 is pivotally connected to the hub 42,` `0f the Y part 3. A spring 19, composed-'of applurality of leaves of'varying length, is-'pivotally Y connected with its roundedfoi'extremities.V toI the vtree ends of the 15, v1.6, whereby a relative vdistortion :of the `parts l and 3 is resisted and these'parts are returned to normal position when the distorting force ceases. The hub 28 is surrounded on its inner-endby a ring 33and an eXtension 32 of this ring enters ahole rovided in the center of the spring :19, w ile two`4 by means of a pin.

ribs 34, extending from the ring 33, have rolling surfaces upon which the inner surface of the spring 19 bears. Upon the leaf spring counter-leaves of appropriate curvature are placed for the purpose of creating a resistance which resiliently brakes the spring on its return to normal position which, consequently, does not take place abiuptly. The leaves of this counter-spring are held together by the extension 32Vsecui'ely held upon the ring by means of the cap 35 mounted upon the extension 32 and secured thereto in any suitable manner, preferably The cap also serves by means of ribs of appropriate forni to maintain the spring iii an appropriate ,initial conditioiiand of graduating the resilient braking and stopping effects. i

In Fig. a the suspension device is shown applied to the rear fork of a bicycle. The horizontal tubes 6, equivalent to the part VG-7 shoivn in Fie'. 1 are iivota-llv connected to the inclined tubes 7 which, in turn, are pivotally connected by the bolt a1 to the part 5. In this instance theleaf spring 19 is also pivotally connected witliits extremities 17, 18 to links 15, 16, respectively, which are pivotally secured to` the parts 5, 7 of the rear fork. In this manner the leaf spring 19 is fulciumed to the pivotal connection of the parts 5, 7 and anyI turning movement of the part 7 with respect to the pai-t 5 is eectively and resiliently opposed by said leaf spring. The pivot pin Ll1 is surrounded by the ring 33 ufliile an eXtension 32, as in the case for the front fork, penetrates a central aperture inthe leaf spring. A counter-spring is also provided bearing on the leaf spring and is held in place by a cap 35 having ribs with suitable rolling surfaces adapted to engage the counter-spring upon the return of the leaf spring to its normal position.

From the foregoing it is evident that under the iniuence of an increasing force the spring will engage with an increasing lengtlitlie rolling surface of the rib 311, so that a constantly decreasing length of the spring will remain free and a braking effect upon the oscillation of the spring is obtained. Upon the retrogressive movement of the spring, when it returns to normal position, a counter-spring is brought into play which effects a braking action upon the leaf spring, and member 35, similar to rib 34, is provided With suitable rolling surfaces so that with increasing force the braking power is correspondingly increased and the oscillations of the spring are effectively avoided.

I am aware that various changes in the arrangement of the parts and their structural forni may be made Without departing from the spirit and scope of the invention, and I Want to avail myself of all such departures which come under the scope of the invention, as pointed out-in the appended claims.

I claim:

1. An elastic suspension device for bicycles, motorcycles, and the like, comprising in combination av fork composed of two parts pivotally connected With each other, a leaf spring having its extremities pivotally connected to said parts and fulcrumed to the pivotal connection thereof, and means engaging said leaf spring to decrease its operative length in proportion to the forces tending to turn one of said parts With retrogressive (movement, andnieans for increasing said braking action. 3.. An elastic suspension device for bicy cles, motorcycles, and the like, comprising in combination a fork composed ofV tivo parts pivotally connected with each other, i,

a leaf spring having its extremities pivotally connected to said parts and fulcrumed to the pivotal connection thereof, and a meniV bei' provided with a rolling surface of suitable curvature engaging said leaf spring such that the power lof said spring is increased in proportion to the forces tending to shift one of said parts in relation to the other. l Y

4. An elastic suspension device for bicy cles, motorcycles, and-the like, comprising in combination a fork composed of tivo parte pivotal-1y Connected with each other, ay leaf spring having its extremities pivotally connected to said parts and-'fulcrumed ,to the pivotalconnectgion tliereof and a ribbed plate member )rovided with a 'rolling surface of suitab e curvature engaging said leaf spring suchY that the operative length of the spring is decreased in proportion to the forces tending to turn one of said parts with respect to the other.

5. An elasticl suspension device for bicycles,y motorcycles, and the like comprising y in combination a fork composed of two parts pivotally connected With each other,

va leaf spring having its extremities pivotally connected to said Vparts and fulcrumed to the pivotal connection thereof, a ribbed plate member provided with' a rolling surface of suitable curvature engaging lsaid leaf spring such that the power of said spring is increased in proportion to the forces tending to turn one of said parts with respect to the other, a counter-spring adapted to exert a braking action upon the leaf spring on its retrogressive movement, and a ribbed plate member aga-inst which the counter-spring is adapted to bear, the area of Contact between the counter-spring and the last named plate member being Varied through the return movement of said 10 leaf spring to normal position.

In witness whereof7V I vhave Yhereunto l signed my name in the presence of twoV subsoribing witnesses. g CARLO BRUNO. Witnesses: l l

vFnmon BAZETTA,

JooELYN Gr'oUBEYRAN.- 

